Manufacture and joining of articles of concrete and the like



July 16, 1935. RUML 2,008,339

MANUFACTURE AND JOINING OF ARTICLES OF CONCRETE AND THE LIKE Filed Jan. 30, 1931 In venfor: jofiogS/a. v T m 2 Patented July 16, 1935 MANUFACTURE AND JOINING OF ARTICLES OF CONCRETE AND THE LIKE l3ohuslav Ruml, Prague, Czechoslovakia Application January 30, 1931, Serial No. 512,467 In Czechoslovakia June 11, 1930 4 Claims. (Cl. 25-155) The subject matter of the invention is a method manometer 34. The emptying oi the concrete as well as an apparatus for the production of container 5 takes only a few minutes or seconds. articles of all kinds, of concrete, ferro-concrete, Accordingly, the air pressure in the concrete conasbestos cement and the like, especially of tubes. tainer 5 must very rapidly be made to conform 5 The appartatisgcgording to the present iaiventoIthe filctltlatilljfii resiisltlance-of the cioncretec.1 t 5 tion is illus ra e y e accompany ng rawn or er o ain e correc an imme is. e ing, of which Fig. 1 shows the whole arrangement alterations of the pressure of the compressed air with the mould in cross-section, Figs. 2 and 3 in the concrete container 5 with respect to the show the mould in cross-section and longitudinal fluctuation of the resistance of the concrete being section respectively, Fig. 4 shows the iron reindelikilleretcii tltie1 corripresssed aiirpipie l is providlel 10 forcement. W1 2. r0 e va ve an a re ucing va ve The mould l, which is in a plurality of parts After the filling of the mould l with concrete and is capable of being dismantled, may be made has been effected, a rapid setting of the outer entirely closed or partly open; it is provided with layers of the concrete body is eiiected by heat.

end walls 2. The core 3, which serves for form- For this purpose there are provided, at the inner 15 ing the hollow space in thelboddy, rlnay be nliade sugfacehgfhthi mould.1 it, longitudgal lclllannels $8 in various ways-e. g., cy in rica conica or in o w c s earn, 0 air or e i e can e prismatic. fed. The setting of the concrete proceeds to the The apparatus further comprises a compressed extent to which the heat spreads from the outer air container 4, into which the compressed air to the inner surface'of the concrete body. At 20 is driven by an air compressor (not shown), and the instant in which the outer layer of the cona container 5 for concrete, the top opening of crete is 111 the hard condition, the inner conwhich is closed by a hi iii that tacts as4 ai check grate llayer isf still plastifc. The 1eilreadly hard valve. The compresse a r con ainer s conu er ayer o concre e orms a rm ase o nected with the concrete container 5 by a comwhich the still plastic inner concrete layer ad- 25 pressed air pipe I. Tgelckoncrete conttainer 5 liertest Tleh cortelnii (far; be withdrawn st this connected to the moul y means 0 a pipe ns an e s p as is innerayer 0 con- .provided with a cock 35. crete ,ofiers only very little resistance on the The method is carried out as follows:- withdrawal of the core 3. The proper length of.

The liquid concrete is driven, by the action of heating of the outer surface of the concrete is 30 the compressed aitrfifromltlhle container 5, thrt'ougl; prgdettelrminec empirically. t b di h h the pipe [2 into e mo e concre e se 11 e pro uc 10m 0 concre e 0 es in w ic in motion has a resistance to overcome which is the formation requires a smooth inner surface, not constant but frequently fluctuates during the withdrawal of the ,core 3 should be proceeded working. At the commencement of working it is with when the inner layer of concrete is very 35 often necessary to set the concrete in motion by near to or Just at the setting stage. If this 1nan increased compressed air action and immedistant is missed, the set concrete embraces the ately after to reduce the air pressure, in order to core so firmly that its withdrawal would be imavoid a local clogging of the mould I. On conpossible.

40 tinued filling of the mould, it is necessary to in- In order to ascertain the correct point of time crease the a P After the filling of the for withdrawing the core, the latter is occasionmould is completed, it is i q t y ne ssa y t ally or continuously rotated. Owing to the conincrease the air pressure in the conta1ner 5 still tinued Setting of the concrete, the friction of the further in order to compress the concrete in the core in the concrete increases and the power closed mould and to drive out the excess of water. necessary for the rotation of the core 3 according The .excess of water then fi F g ly also increases. This growing consumption of gfif g i 6 mg 5 power is measured-e. g., with the aid of. an

The magnitude of the air pressure in the conif i a? if fzgiiigs g i i ffiz tainer 5 is further dependent upon the thickness i a th t g Y 50 of concrete and the length of the hollow body, core s F g i collar? h fie upon the height from which the concreteis dez i g gl g tte ccgilcre e, e coe 1sI fat so ea 6. livered, upon the frictional resistance in pipe I2, an S lame Increase e and upon the water content of the concrete. This before being wlthdlawn from the onc e e, i

55 magnitude of air pressure is controlled by using a cooled by admission of cold water or the like, it 55 contracts to its original diameter and its withdrawal is thus further facilitated.

In order that the mould which is made or a number 01 parts should not come apart during the filling oi. the concrete body owing to the internal pressure then developed, the mould is secured by a rope 29 which is helically wound on its outside and which is fastened at its two ends to hooks 30 iittedjn the outside of the mould (Fig. 3)

In the case of the production of concrete bodies with iron reinforcements 3l32, the latter are fixed in position by rings of concrete 33 (Figs. 2 and 4) mounted or pressed on at suitable intervals which rest against the core during the filling of. the mould and serve as guides for the core during its removal, being embedded with their outer portions in the hardened outer layer of the concrete body.

The concrete body is left in the mould until the hardening is ended. The rope 29 is then unfastened and removed and the mould is dismantled.

What I claim and desire to secure by Letters Patent of the United States 01 America is:

1. A method for facilitating the withdrawal of the core during the manufacture or hollow articles oi! all kinds made of concrete, ferro-concrete, asbestos-cement and the like, especially of tubes, comprising heating only the outer concrete layer oi the body in order to accelerate the setting of the outer concrete layer with regard to that of the inner concrete layer.

2. A method according to claim 1 wherein during the heating of the surface oi the concrete, the core is occasionally or continuously rotated and the consumption of power necessary for rotating the core is measured for the purpose of checking the progress of the setting of the concrete.

3. A method according to claim 1 wherein the core is withdrawn from the concrete body at the point of time at which the outer surface is hard and the inner surface is still soft. I

4. A method according to claim 1 applicable to the manufacture of hollow articles oi. ierro-concrete containing metal reinforcing rods, wherein reinforcements are fixed in position by rings of. concrete mounted thereon, which rest against the core during the filling of the mold, and serve as guides tor the core during its removal.

BOHUSLAV RUML. 

